After reading AN 10.177 i would like to ask if some one know how to do offerings to dead relatives in ghost realm or other. If there is some ritual, some tipe of offerings, just mental offerings, if it takes a form of wishes, or other?

I think generally you just make offerings to the Sangha and then dedicate the merit to the relatives. There might be a traditional verse to recite for the dedication but I don't actualy know what it is.

The non-doing of any evil, The performance of what's skillful,The cleansing of one's own mind: This is the Buddhas' teaching.

If you are in the country where you can find monk in (Theravada), food offering, any donation to the temple are the ways. If not, you can donate money or belongings to person in need. It is not difficult to find any charity organization in your area or even search on the web the organization that you like best.

There is no official ritual in offerings to dead relatives, though there is some pali phrase about that. But it is not about the saying in language that you even don't understand to complete the process. It's about your intention.

Words that you can say or think (recite in your thought) before, during, and after such donations can be in the following way: With the good deeds I have done, I would like to consign merit to ..................... (your relatives' name). May he/she acknowledge and rejoice the good deed that I have already done.

ฺBasically, every good deeds, act can be consigned to the dead. The donation seems to be the most convenience one. There are what we called 10 bases of meritorious action, if you have done any of them, you can consign to your relatives and other who had passed away.

bases of meritorious action) 1. meritorious action consisting in generosity; merit acquired by giving 2. by observing the precepts or moral behavior 3. by mental development 4. by humility or reverence 5. by rendering services 6. by sharing or giving out merit 7. by rejoicing in others’ merit 8. by listening to the Doctrine or right teaching 9. by teaching the Doctrine or showing truth 10. by straightening one’s views or forming correct views

My deceased wife loved Jelly Belly brand jelly beans. I buy them and place them on our headstone, whenever I am near her burial site. I think my daughter eats them, though, because they are gone when I stop to say goodbye before going home.

Even if the dead do not eat our food offerings, for me it is the thought of giving thanks for all the love and kindness she showered on me while she was alive. From my experience, 'tis the most burdensome attachment of all, when someone you really loved dies.

What Makes an Elder? :A head of gray hairs doesn't mean one's an elder. Advanced in years, one's called an old fool.But one in whom there is truth, restraint, rectitude, gentleness,self-control, he's called an elder, his impurities disgorged, enlightened.-Dhammpada, 19, translated by Thanissaro Bhikkhu.

More: there are ways in doing, practicing good deeds even if you are in the place where accessing to Theravada temple is not convenience. Doing good can be done in daily life. Here are the writing explaining in details about the TEN BASES OF MERITORIOUS ACTION